Q.What is a concept? Explain the role of concept in the thinking process.

A concept is the mental representation of a category — a class of objects, ideas or events that share common properties, which the mind uses to identify and make sense of whatever it encounters. When a new or unfamiliar object or event comes up, the mind tries to identify it by extracting its distinguishing characteristics and matching them against categories already held in memory; if the match is close enough, the object is given the name of that category. Coming across a small, unfamiliar four-legged, dog-faced creature that wags its tail and barks at strangers, for instance, leads most people to classify it as 'a dog' (perhaps a breed they have not seen before), and once that category has been applied, further expectations follow automatically — such as expecting the animal to bark at other strangers too, even without having tested this directly. This shows that a concept is not just a label; it carries a bundle of associated properties and expectations that get applied the moment an object is categorised.

The role concepts play in the thinking process is chiefly one of efficiency. Rather than analysing every object or event completely afresh each time it is encountered, having a ready stock of concepts lets information already known about a category be retrieved and applied quickly, with far less time and mental effort. This is compared in the chapter to organising physical belongings — a child who keeps books, pens and other items in specific, labelled places in a cupboard does not have to search at random each morning, and a library that shelves and labels its books by subject area lets a reader find what is needed with minimal effort. In just the same way, forming concepts and sorting objects and events into them is what makes a person's thought process quick and efficient rather than slow and effortful, and concepts (together with mental images) form the basic material that the higher-level thinking processes discussed later in the chapter — problem solving, reasoning, decision-making and creative thinking — are all built out of.